1. Field of the Invention
This invention relates to compositions containing an active or functional organic compound which requires solubilization, and more particularly, to compositions which are effectively solubilized by addition of an ester of an aryl alcohol, e.g., phenethyl, benzyl or substituted benzyl alcohol, and an alkyl or cycloalkyl carboxylic or carbonic acid.
2. Description of the Prior Art
Many commercial products such as personal care (e.g., sunscreens or UV filters), pharmaceutical, agricultural and industrial compositions, contain active or functional materials which require solubilization in the form of a solution, emulsion or dispersion, in aqueous or non-aqueous form. For example, a sunscreen formulation containing aromatic compounds such as Avobenzone (Butyl methoxydibenzoylmethane, Escalol® 517) and/or Oxybenzone (Benzophenone-3, Escalol® 567) as active UVA/UVB absorbing ingredients requires a solubilizing agent to keep them in an emulsion, i.e., to prevent crystallization. Several such solubilizers are known, e.g., C12-15 alkyl benzoate (Finsolv® TN); however, they are mediocre solubilizing agents and/or have a ‘heavy’ feel, which is undesirable in modern cosmetic formulations.
H. Gers-Barlag et al. in U.S. Pat. No. 6,770,269 described a solubilizing agent for triazine derivatives which was an ester of an unbranched alkyl carboxylic acid and a mono- or polybranched aliphatic alcohol, particularly hexyldecyl laurate, which was derived from lauric acid and hexyldecyl alcohol. Previously, the same authors in U.S. Pat. No. 6,703,001 had described a solubilizing agent for triazine derivatives which was an ester of a branched-chain carboxylic acid and a branched-chain alcohol, particularly isodecyl neopentanoate, which was derived from neopentanoic acid and isodecyl alcohol.
I. Walele et al. in U.S. Pat. No. 6,635,775 described a process for “reduced odor esters” which improved the preparation of established cosmetic esters such as C12-15 alkyl benzoates and cetearyl octanoate.
We have previously disclosed in U.S. patent application Ser. No. 11/007,744 that esters of aryl carboxylic acids and aryl alcohols, particularly phenethyl benzoate, which was derived from benzoic acid and 2-phenylethanol, are superior solvents for actives such as sunscreens or UV filters. It was nevertheless surprising, and it could not have been predicted by someone skilled in the art, that combinations of actives with esters of alkyl (including cycloalkyl) carboxylic acids and aryl alcohols would likewise be superior solvents. Completely unprecedented was the discovery that the cyclopropyl group, e.g., in 2-phenylethyl cyclopropanoate; which was derived from cyclopropanecarboxylic acid and 2-phenylethanol, imparts remarkable solubilizing power for the triazines, e.g., Ethylhexyl triazone and Bis-ethylhexyloxyphenol methoxyphenyl triazine.
Accordingly, it is an object of this invention to provide a composition including an active or functional organic compound which is solubilized by a safe and effective organic ester or carbonate as solvent, cosolvent or additive.
Another object is to provide a personal care composition, e.g., a sunscreen or cosmetic composition, or a pharmaceutical, agricultural or industrial composition, containing a solid active or functional organic compound, which is effectively solubilized by an ester of an aryl alcohol, e.g., phenethyl, benzyl or substituted benzyl alcohol, and an alkyl or cycloalkyl carboxylic acid, or a carbonate of an aryl alcohol and an alkyl or cycloalkyl carbonic acid.
A specific object herein is to provide a sunscreen composition containing active UVA and/or UVB compounds which are effectively solubilized by the esters or carbonates of the invention.
These and other objects and features of the invention will be made apparent from the following description.